We all know the drill: Slip up on your regular brush-and-floss routine, and you may end up at the dentist's office with a cavity that needs to be filled. But what people did about their toothaches thousands of years ago?

Scientists in Italy have discovered what may be the earliest evidence of therapeutic dentistry performed on a human.

The discovery of a planetary "odd couple" is broadening the way scientists think about planetary migration.

Scientists at the Harvard Smithsonian Center for Astrophysics and University of Washington discovered two planets of very different sizes and makeups orbiting Kepler-36, a sun-like star under nearly continuous surveillance by the Kepler spacecraft.

"This is kind of an extreme system in that the planets are relatively closely spaced in their orbits but their compositions are quite disparate," said Josh Carter, Hubble Fellow at the Harvard Smithsonian Center for Astrophysics who discovered the smaller planet.

Curiosity, NASA's rover bound for Mars, is set to touch down in August. Now, scientists say they know with even more accuracy where it will land.

The summer landing will be the start of a Martian road trip that will take months or possibly a year as Curiosity makes its way toward its final destination, the Gale Crater, said Curiosity contributor James Wray, an assistant professor of Earth and Atmospheric Science at the Georgia Institute of Technology.

"The most important thing perhaps is that we are steering to a different place in Gale Crater, which is a giant mountain of sedimentary rock," Wray said. Unlike Curiosity's predecessors, Opportunity and Spirit, "We are going with the intention of having to drive a long distance before even getting to what we want to study because the mountain is too steep," Wray said.

Researchers at the University of Colorado have made a breakthrough that may one day help doctors detect disease earlier and with more accuracy.

Based on the hypothosesis of Dr. Tenio Popmintchev, researchers have created a laser beam by adding 5,000 photons together. Previously, two photons were typically used to create laser beams. This is the first time so many photons have been successfully added together.

The result is a more efficient and easier to set up X-ray, according to Dr. Margaret Murnane.

"If we can push this further, and we don’t know how far into the X-ray region we can push this technology, there's a chance we can change your doctor or dentist's X-ray device to a laser version." Murnane said.

"The image would be much crisper. It could really get high resolution X-rays so you could detect disease much earlier."

But that is still a while away - possibly around 10 or 20 years guessed Murnane.

In the meantime, the breakthrough sheds light on how heat flows in very small devices, which may allow scientists develop more energy efficient data storage devices, better understanding of solar energy harvesting and better nano electronics, "so your laptop doesn't heat up so fast," Murnane said.

Our Milky Way galaxy is an anomaly in more ways than one. And now, NASA scientists say they know exactly when it will come to an end.

In a universe that is forever spreading apart, the Milky Way has been moving closer to celestial neighbor the Andromeda galaxy. But whether we are in for intergalactic Armageddon or an extraterrestrial fender bender has been a mystery - until now.

“Very interestingly, we find that Andromeda galaxy does appear to be coming straight at us,” said Roeland van der Marel, an astronomer at the Space Telescope Science Institute in Baltimore. He was scheduled to speak at a NASA press conference Thursday.

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